J. Neurol. Neurosurg. Psychiat., 1957, 20, 40.

A VARIETY OF PARAMYOTONIA CONGENITABY

E. B. FRENCH and R. KILPATRICKFrom the Eastern General Hospital, Edinburgh

Paramyotonia congenita was first described byEulenberg (1886). It is a rare, hereditary disorder ofmuscle in which severe loss of power is induced bydegrees of cooling which are insufficient to affectnormal muscle. Myotonia also appears on cooling.However, the paralysis produced by cooling dis-tinguishes paramyotonia from Thomsen's disease.The weakness and myotonia can easily be producedunder controlled conditions so that the disease lendsitself to investigation. In spite of this fact, fewobservations have been made and nothing is knownabout the fundamental defect. The present case of aman aged 51 years is of particular interest becauseof certain additional features, and a personal andfamily history of generalized attacks of weaknesssuch as occur in familial periodic paralysis. The casehistory is presented in full and is followed by someobservations on the induction and relief of paralysisand myotonia.

Case ReportPersonal History.-Myotonia has been present since

infancy, for it was noted that his eyes did not opennormally after a fit of crying. As long as he can remem-ber he has suffered from a combination of myotonia andweakness on exposure to cold. The condition was generalor local according to the extent of the cooling. Thus10 minutes in a swimming pool made him helpless; hecould not work off the effects by exercise and his move-ments were weak as well as stiff. At school in the wintertime he found it difficult to write or to stand up suddenly.If he was warmly clad but his face was cooled, he foundthat after smiling or sneezing his face would remaincontorted, and he used to cover his face with a handker-chief on such occasions to avoid social embarrassment.In the summer, as a youth, he took a leading part inamateur wrestling, but he was unable to do so in winter.He believes that the symptoms induced by cold are lesssevere now than when he was a child. He still findsdifficulty in speaking in cold weather, and dysphagiaresults from drinking cold liquids. Chewing is alsoaffected, sometimes by inability to relax after a bite, atother times by weakness which he overcomes by pushingup his jaw with his hands. He states that myotonia passesoff when he warms up, but that weakness persists forsome hours. Irrespective of temperature he has at all

times been able to produce myotonia of the eyelids byshutting them tightly for several seconds.He describes about 12 attacks of paralysis resembling

familial periodic paralysis, which occurred when he wasbetween 8 and 20 years of age. Most of the attacks werepresent on awakening. In some an arm, a leg, or bothlegs only were paralysed, in others all four limbs, thetrunk, and the neck were involved. He could alwaystalk, eat, and empty his bowels and bladder normally.Paralysis lasted for two or three days, during which timehe had to be fed, and complete recovery occurred withina week. Because of one of these attacks he was senthome from a scout camp with a diagnosis of polio-myelitis. The usual precipitating factor was exerciseduring the previous evening. When paralysis was in-complete, he could work it off by exercising the partaffected. Attacks occurred at all seasons of the year, andhe recalls one attack occurring in day time after sun-bathing.

In November, 1949, he attended with persistent weak-ness of the right leg and some wasting of the calf. InAugust, 1950, he complained of difficulty in climbingstairs and in rising from a chair. In October, 1951, bothlegs were weak, and wasting was present in both calves.From then until the present time there has been pro-gressive wasting of the legs and of the lower halves of thethighs. He is now apt to trip over irregularities of theground and he is unable to rise again without assistance.

Family History.-A genealogical tree of the family isshown in Fig. 1. The information for this was given bythe patient, and none of the other members has beenexamined. All the living members are strikingly un-cooperative and would not permit even an interview toelicit a medical history. This reluctance was previouslyshown by the patient, as his condition escaped noticewhile he was in hospital in June, 1949, suffering frompneumonia. The patient is only certain about the presenceor absence of myotonia in the family, and thus only thisabnormality is included. In addition some have weaknessinduced by cold, but he is uncertain about its presenceor absence in others. His grandfather (11.2) was foundto have contracture of the calf muscles when he wasadmitted to hospital for some other condition, andbilateral tenotomy was performed. One maternal aunt(111.5) also developed wasting of various muscles, inaddition to life-long myotonia and weakness on cooling.The inheritance of the myotonia is clearly due toautosomal dominance, as has been previously noted

40

Protected by copyright.

on August 24, 2021 by guest.

http://jnnp.bmj.com

/J N

eurol Neurosurg P

sychiatry: first published as 10.1136/jnnp.20.1.40 on 1 February 1957. D

ownloaded from

A VARIETY OF PARAMYOTONIA CONGENITA

I

Jr1

'i

174 19120 21 22

s

FiG. 1.-Genealogical tree showing inheritance of myotonia byautosomal dominance. 0 MYOTONIA

(Thomasen, 1948). However, in rare instances, Thomasenfound recessive inheritance. Various factors, such asminimal symptoms, memory, legitimacy, or mutationmay account for the recorded absence of myotonia ineither of the two great grandparents.

Physical Examination.-The muscular development ofthe upper part of the body contrasted with the wastingof the legs. The front half of the scalp was bald andthere was a patch of occipital baldness, which was notunreasonable for his age. Pubic and axillary hair werenormal, and hair was present on the chest, arms, andlegs. Both testes were very small. The breasts werenormal and the thyroid gland was not enlarged. Thecardiovascular system and an electrocardiogram werenormal. Renal function was unimpaired. The dailyurinary excretion of 17-ketosteroids was 14-0 mg. and of17-hydroxycorticosteroids was 6-7 mg. Estimation ofgonadotrophic hormone excretion in urine was alsonormal for his age.

His intellectual functions and sensory examinationwere normal. Ophthalmological examination was kindlyperformed by Dr. G. I. Scott and he found no cataractor disturbance of vision. After strong contraction ofthe orbicularis oculi had been maintained for severalseconds the patient was unable to open his eyelids. Thisdelay in relaxation passed off gradually in about twominutes. It persisted even with repetitive contractions.The clavicular heads of both sternomastoid muscles weremoderately wasted and there was slight weakness offorward flexion of the head.

Upper Limbs.-No wasting was evident, but the flexormuscles of the right forearm were abnormally firm andthere was shortening, as he was unable to extend theinterphalangeal joints when the wrist was dorsiflexed.

'G DIED IN INFANCY

Power of all movements was reduced, particularly of thedistal muscles. His grip, measured by the methoddescribed later, was less than half of that of several malestudents. Muscle tone was normal. The tendon jerkswere very feeble.Trunk.-The power of flexion was good, but extension

was impaired. The abdominal reflexes were absent.Legs.-There was bilateral pes cavus. When the

patient stood upright with the feet together, the heelswere 4 cm. from the ground, due to wasting, hardening,and shortening of the calf muscles. The anterior tibialgroups were slightly wasted. There was atrophy of thelower half of the quadriceps muscle on each side, par-ticularly of the vastus medialis. Tone in the musclesunaffected by fibrosis was normal. Knee and ankle jerkswere absent; plantar responses were flexor.

Electrical Excitation.-Several of the affected muscleswere tested by use of the Ritchie-Sneath stimulator. Somereaction of degeneration was present, such as has beenrecorded previously in cases of dystrophia myotonica,and after cooling there were changes characteristic ofmyotonia (Brain, 1955).

Effect of Various Procedures in Measuring Weakness andMyotonia

Power of Grip.-Power of grip was measured by askingthe patient to squeeze a rubber bulb with maximum forcefor two seconds. The force was transmitted throughrubber pressure tubing to a tambour on which was sealeda lever which recorded on a kymograph. A side-armopening in the tubing, which was only closed for eachcontraction, gave a constant base line even when thebulb was held in cold or hot water. The response of thepatient to the abrupt commands-" grip ", " relax"

41

Protected by copyright.

on August 24, 2021 by guest.

http://jnnp.bmj.com

/J N

eurol Neurosurg P

sychiatry: first published as 10.1136/jnnp.20.1.40 on 1 February 1957. D

ownloaded from

E. B. FRENCH AND R. KILPATRICKwith two seconds between them gave a smooth curveand a remarkably constant response. Deflection upwardsdenoted gripping and deflection downwards denotedrelaxation. The system was calibrated against a mercurymanometer and over the range of power shown by thepatient the height of the response bore a linear relation-ship to the pressure within the bulb. The rate of fall ofthe curve after the command " relax" gave a clear indi-cation of myotonia, but an accurate measure of thedegree of myotonia was impossible when weakness wassevere. Room temperature for all observations was20° C. A satisfactory method was evolved for recordingflexion of the ring finger in response to stimulation of theulnar nerve of a normal person. When this was appliedto the patient his base line weakness was such thatscarcely any movement of the finger could be seen andno movement of the recording system could be obtainedon maximal stimulation of the ulnar nerve. Changes inmuscle temperature produced by immersion in cold orhot water were measured by a thermistor soldered in thetip of an intramuscular needle. This was calibrated beforeeach measurement by immersion in water at a knowntemperature.

Local Cooling.-One forearm was cooled in waterwhilst the rest of the body was kept warm; the grip of thecooled arm was affected by weakness and myotonia;the grip of the other arm was unaffected. The rate ofonset and the intensity of the effects were greater as thetemperature of the water was reduced. Weakeningoccurred at 280 C., but it was slow in onset and slight indegree.

Prolonged Forearm Cooling at 12 5 C.: Recovery inAir at 20° C. For subsequent observations on coolinga temperature of 12.50 C. was selected as it producedlittle discomfort and a conveniently rapid onset ofparalysis. Either forearm was immersed in water in alarge sink, and the temperature was kept approximatelyconstant with no stirring by floating a few pieces of icein the water.

Paralysis was nearly complete after 40 minutes' cooling.

The rubber bulb placed in the weakened hand could beretained only with difficulty. Recovery at room tempera-ure was incompltete after several hours.

Prolonged Forearm Cooling: Recovery in Water at40° C.-This was studied in the patient and two groupsof controls.

Patient.-After 38 minutes in water at 12-50 C. thearm was plunged into hot water at 400 C. The gripbecame weaker for the first five to 15 minutes in hotwater, and then power returned gradually to its initialvalue after warming for 25 minutes. However, the severemyotonia produced by the cooling passed off within fourminutes of transferring to hot water, at a time whenpower was still diminishing (Fig. 2).Two Normal Males.-Cooling at 12 50 C. for 40

minutes did not cause any change in power which couldbe measured by the method employed. If, however, theforearm of a normal subject was immersed in water at90 C., measurable weakness of grip and difficulty inrelaxation developed in 20 minutes. Power was reducedto 53% after one hour, and four minutes after trans-ferring to hot water was 88 % of normal power.Two Male Patients with Dystrophia Myotoniica.-No

weakness was detected after cooling for 40 minutes at12.50 C.

Ischaemia.-Occlusion of the patient's brachial arteryby a cuff at 200 mm. Hg with the arm in water at 350 C.resulted in paralysis in 20 minutes. Release of the cuffwas followed by complete recovery in three minutes.This was comparable with a normal person.

Cooling of Ischaemic Arm at 12.50 C. for Five Minutes:Recovery in Hot Water (40-44° C.).-It was noted bythe patient and by clinical observation that when thecirculation was released after cooling the ischaemic fore-arm for five to 10 minutes at 12 5° C. there was lessdisability than when a free circulation was presentthroughout. The difference was more obvious if bloodwas expressed from the arm by an Esmarch bandage

(a) (b) (c) (di)FIG. 2.-(a) Grip after 38 min. in water at 130 C. showing myotonia and weakness. (b) Grip 14 min. after subsequent transfer intowater at 390 C. Myotonia has passed off: weakness still present. (c) Patient's normal grip. (di) Grip takeii 1-5 min. after immersionof ischaemic arm in water at 12 5° C. for five min. showing myotonia and slight weakness.

42

Protected by copyright.

on August 24, 2021 by guest.

http://jnnp.bmj.com

/J N

eurol Neurosurg P

sychiatry: first published as 10.1136/jnnp.20.1.40 on 1 February 1957. D

ownloaded from

A VARIETY OF PARAMYOTONIA CONGENITA

TABLE

EFFECT OF ISCHAEMIA ON WEAKNESS PRODUCED BY 5 MINUTES' COOLING IN WATER AT 12-50 C. ANDRECOVERY IN WATER AT 400 C.

Power of Grip Mean Power of Mean Power of Mean Power of Mean Power ofNumber of before Cooling Grip I Minute Grip 6 Minutes Grip 11 Minutes Grip 16 MinutesObservations as Height in after Cooling after Cooling after Cooling after Cooling

Centimetres (% Control (% Control (% Control (% ControlRange Reading ± S.E.) Reading ± S.E.) Reading ± S.E.) Reading i S.E.)

Arm with circulation intact 8 2-9-4-3 78± 55 72±6-7 73 ± 5-2 77±4-2during cooling

Arm with circulation oc- 3 2-3-3-3 88 13-3 101±7-1 111±8-6 113±8-8cluded during cooling

before cooling. Cooling for five minutes was the optimumtime for bringing out this difference and no weaknessdue to ischaemia without cooling occurred in so short aperiod. Both because the resulting difference in powermight be attributable to reactive hyperaemia and in orderto prevent further cooling, the arm was plunged into hotwater as the ischaemia was released. The results arecompared with the opposite arm treated similarly exceptfor the ischaemia (Fig. 2) and are shown in the Table.With the circulation intact, the power decreased slightly

after cessation of cooling and going into hot water.However, using approximate test of significance (dif-ference between means compared with 1-5 x sum ofstandard errors of means) this further fall is not signifi-cant. Mean power is greater at all times after coolingwith the circulation occluded. However, using the abovetest, only the differences at six, 11, and 16 minutes aftercooling are statistically significant. Thus the ischaemicarm still develops slight weakness after cooling, but hasreturned to normal six minutes after cooling, whereasthe non-ischaemic arm is still weak after the 16 minutes.The effect of ischaemia on the weakness caused by

cooling might result from differences in the degree or therate of cooling or rewarming. These possibilities werestudied using the forearm of a normal subject.

Muscle Temperature during Cooling and Reheating in aNormal Subject.-The arm was cooled at 12-50 C. forfive minutes and then heated in water at 40 to 440 C. asdescribed above. Muscle temperature was measured atvarious depths in the midline of the flexor muscle massof the forearm, 3 cm. below the elbow.At a depth of 2 cm. the average fall in temperature was

0.75° C. (20 observations). After plunging the arm intohot water the temperature remained steady or fell a littlefurther during the next four minutes and then began torise to the original level after a further four to six minutes.At this depth heat is evidently lost to the colder super-ficial layers at a greater rate than it is supplied by theblood.

Measurements made at a depth of 1 2 cm. showed anaverage fall in temperature of 2.60 C. (four observations).After transferring the arm to hot water the temperaturebegan to rise within one minute, returning to the originallevel in five minutes and rising 1.50 C. above it in thenext five minutes.There was no difference between the ischaemic and the

unoccluded arms. It seems clear, therefore, that a risein temperature due to reactive hyperaemia in muscle inthese circumstances is negligible.

Fatigue.-Fatigue of the grip was induced by makingmaximum voluntary contractions of the rubber bulb onceper second, and taking a record every minute. In bothpatient and normal subjects power was reduced by onehalf after six minutes. Some improvement in poweroccurred after one minute's rest, but the return to normalpower was slow and was incomplete after 25 minutes.No difference between the patient and normal subjectswas found in these tests.

Chemical Constituents of the Blood after Cooling.These were measured generally and locally.

General Cooling.-The patient was immersed up to theneck in a bath at 210 C. for 10 minutes, after which thearms, legs, and trunk were so weakened that it wasnecessary for two people to lift him out of the bath andassist him to bed. For the first hour after removal fromthe bath, the weakness became even greater. After im-mersion there was no change in the serum potassiumlevel or an E.C.G.Forearm Cooling.-Blood was obtained from the

median cubital vein immediately before and after coolingone forearm for 20 minutes and at the same time fromthe uncooled arm. There was no change in the bloodglucose, plasma phosphorus, serum sodium, potassium,and creatine levels in the blood from either arm.

Effect of Drugs upon the Patient.-Glucose, adrenaline,neostigmine, quinine, and potassium chloride were thustested.Glucose.-A dose of 50 g. was given but no subjective

or objective change in power took place over the nextthree hours.Adrenaline.-A subcutaneous injection of 0-6 mg.

adrenaline was followed by a slight increase in powerafter 10 minutes, which was sustained for 20 minutes.

Adrenaline did not prevent or diminish the weakeningeffect of cooling.Neostigmine.-A subcutaneous injection of 2 mg.

neostigmine was followed after 25 minutes by generalizedmyotonia. The patient dared not swallow, for previousexperience had taught him that his breathing wouldbecome obstructed. He sat with his head forward, withsaliva dripping from his mouth and saying little, andthat in a low, husky voice. One grip was recorded whichshowed myotonia but no weakness. It cannot be saidthat no decrease in power would have occurred subse-quently for his distress made it imperative to terminate

43

Protected by copyright.

on August 24, 2021 by guest.

http://jnnp.bmj.com

/J N

eurol Neurosurg P

sychiatry: first published as 10.1136/jnnp.20.1.40 on 1 February 1957. D

ownloaded from

E. B. FRENCH AND R. KILPATRICK

*:' i.

the observation. Quinine was given intraverivusly andthe myotonia passed off rapidly (Fig. 3).

Quinine.-Quinine sulphate, 1 g. t.i.d. xed asubjective improvement on cold days, bi. A ijectiveimprovement of power or of weakness due o coolingcould be demonstrated. Myotonia no longer( -curred inthe forearm after cooling. The myotonia of-the eyelidswas unaffected; the strong and long contraction required,its persistence after repeated contractions, and the lackof response to quinine suggest myotonia paradoxa ofthe eyelids (Marshall, 1952).Potassium Chloride.-The patient was given 5 g.

potassium chloride t.i.d. as an out-patient in the beliefthat his condition might be improved. He stated thatafter two doses he developed generalized weakness.Later in hospital he was given 5 g. potassium chlorideby mouth before breakfast. About 1-5 hours later hebecame weak, was unable :o sit up in bed withoutassistance, and had difficulty in coughing. The trunk andleg muscles were greatly weakened and remained so for afew days. The grip was reduced to less than half (Fig. 4)but improved several hours later. Myotonia was notincreased at any time. The serum potassium was5-2 m.Eq./l. before the dose was given and 5-0 m.Eq.l.

FIG. 3.-Atropine sulphate, I mg. sub-cutaneously; neostigmine, 2 mg.subcutaneously 10 min. later:(a) 17 min. after neostigmine; gripstill normal; (b) 32 min., myotoniapresent showing step-like relaxationphase; power normal; (c) 42 min.,normal grip a few minutes after0 5g. quinine hydrochloride intra-venously.

two and a half hours later when he was very weak. Thepatient was greatly alarmed by this effect and though hehad been very cooperative throughout a period of fiveyears he was unwilling to undergo further trials of potas-sium chloride. Potassium balance studies were not madeowing to the lack of suitable facilities. It might be thoughtthat the apparent effect of potassium chloride washysterical in origin. Clinical observation convinced usthat this was not the case. In addition, the recovery ofpower was steady over a period of hours, the patientbeing placed in such a position that he could not see theheight of each previous record. Moreover, attempts torecord submaximal grips invariably resulted in an irregu-lar upper limit of the curve quite unlike the smooth typeof curve recorded in the figures. Irregularity of relaxationin the presence of myotonia was often recorded and is afeature which has been noted by others (Ravin, 1939).It is therefore beyond all reasonable doubt that the ob-served effect of potassium was genuine.

Cortisone.-In view of the ill effects of potassium,it was thought that cortisone might improve his con-dition. In addition, Shy and McEachern (1951) havereported improvement of senile myopathy by cortisone.He was given cortisone acetate, 200 mg. daily by mouth,

Fso. 4.-(a) Normal grip before 5 g. potassiumchloride orally. (b) Same arm 2-5 hours later.showing weakness but no myotonia.

44

I

Protected by copyright.

on August 24, 2021 by guest.

http://jnnp.bmj.com

/J N

eurol Neurosurg P

sychiatry: first published as 10.1136/jnnp.20.1.40 on 1 February 1957. D

ownloaded from

A VARIETY OF PARAMYOTONIA CONGENITA

for three days, diminishing to 12-5 mg. on the tenth day,up to a total of I g. There was no objective improvementin power or the reaction to cooling. Later he took 25 mg.cortisone daily for two months and was enthusiastic aboutthe results at first. However, there was no improvementin his grip and at the end of the course he did not returnfor further supplies as he was putting on too muchweight.

DiscussionThe hereditary disorder from which this man

suffers has some of the features of dystrophiamyotonica. There is myotonia, muscle wasting,testicular atrophy, and frontal baldness. There is,however, no sign of cataract in spite of his age, nomyopathic facies, and there is not a striking atrophyof the sternomastoid muscles.The attacks of paralysis during childhood and

adolescence suggest familial periodic paralysis.Muscular atrophy has been recorded late in thecourse of this disease (Biemond and Daniels, 1934).Both glucose and adrenaline failed to precipitate anattack of paralysis, but the patient was not havingclinical attacks at the time of investigation. Theeffect of potassium was tried in the hope that theweakness might be improved or that paralysis inresponse to cold might be prevented. Instead ofimprovement a prolonged attack of generalizedweakness developed after 5 g. of potassium chloride.Myotonia was not aggravated, though Russell andStedman (1936) produced severe myotonia in a caseof Thomsen's disease by oral administration of 5 g.potassium chloride. Kolb, Harvey, and Whitehill(1938) could not demonstrate any effect of potassiumon the myotonia in dystrophia myotonica. Muscularparalysis associated with low, or more rarely, withhigh levels of serum potassium is well known. Thusan attack in a patient subject to periodic paralysis isusually accompanied by a transfer of potassium tothe intracellular phase and a fall in the serum con-centration. However, there is a poor correlationbetween the onset and the severity of the attacksand the magnitude of the depression of the serumpotassium level (Talbott, 1941). There have beenoccasional reports of a clinical syndrome resemblingperiodic paralysis in which no change in the serumpotassium level occurred during attacks. In onesuch family, oral potassium chloride caused a vaguelack of well-being and did not prevent attacks, sothat all the patients discontinued the treatment aftera few weeks (Tyler, Stephens, Gunn, and Perkoff,1951). By contrast, in other conditions such asdiabetic coma under treatment with insulin, theconcentration of potassium in the serum may fallto levels far below those commonly found during anattack of periodic paralysis, and yet paralysis does

not commonly occur. In these circumstances thecellular content of potassium is also lowered. Thereare a number of case records in the literature showingclose similarity with various features of the presentcase, but we can find no previous record of paralysisbeing caused by a therapeutic dose of potassiumsuch as that employed in the present case.The features shown by this patient are similar to

those described by Eulenburg (1886). He recordedthe muscle disorder inherited as a dominant charac-ter without sex-linked inheritance, which he namedparamyotonia congenita. Almost all the musclesbecame stiff and weak after prolonged cooling anddid not regain normal power for several hours, evenafter rewarming. Generalized attacks of weaknessalso czlcurred but always in response to cold. Hecomp -d the condition with familial periodicparalvsis'. He could not demonstrate active ormech 11' induced myotonia. However, certainmusc; v"ved spontaneous tonic contraction whencoolect -iample, these patients experienced toniccontracti.ds of the orbicularis oculi and oris whenexposed . a cold wind. Schott (1935) investigated apatient with paramyotonia. When warm, musclefunctionwas normal; on cooling, irritability increasedas in Eulenburg's family, but at the same time activemyotonia appeared; after prolonged cooling heclaimed that myotonia gradually decreased as paresisincreased. Thus we would classify the present caseas a variety of paramyotonia. The dissimilaritiesare that some myotonia is always present, and thatgeneralized attacks of weakness, which were notapparently related to cold, had previously occurred.Weakness from local cooling has also been re-

ported in familial periodic paralysis. Zabriskie andFrantz (1932) reported the effect of cooling of theforearm in a young man suffering from a clinicalsyndrome resembling familial periodic paralysis.After 12 minutes in water between 100 and 140 C. itwas noted tha relaxation of the flexors of the fingersafter voluntary contraction was distinctly slow.After 35 minutes paralysis was practically completeand recovery was incomplete 12 hours later. Heatingthe paralysed limb in water at 400 C. restored normalpower in one h( 4r. Similar observations are reportedby Bickerstaff (.;'53). McArdle (1956) reports thatlocal cooling pr9duced gross local weakness inperiodic paralysis, which wjs not due to locallowering of serum potassium. This is further evi-dence against the primary disorder being a defectin potassium metabolism.The coincidence of various rare features in the one

patient and the occurrence of several of them inmany other members of the family supports the viewthat myotonia congenita, dystrophia myotonica, andparamyotonia congenita are variants of the same

45

Protected by copyright.

on August 24, 2021 by guest.

http://jnnp.bmj.com

/J N

eurol Neurosurg P

sychiatry: first published as 10.1136/jnnp.20.1.40 on 1 February 1957. D

ownloaded from

E. B. FRENCH AND R. KILPATRICK

hereditary defect (Maas and Paterson, 1950;Stevens, 1954). The features also suggest a relation-ship to periodic paralysis, where the primary defectis probably in voluntary muscle.The patient's history suggests that the myotonia

and the weakness usually appear together, and thisis certainly true in response to cooling. Our observa-tions enabled us to separate these two features.It has been mentioned that weakness with nodemonstrable myotonia followed the ingestion of5 g. potassium chloride; unfortunately we wereunable to find a rapid method of relieving the weak-ness produced. Myotonia was precipitated byneostigmine and abolished by quinine, but no weak-ness occurred. Warming of the cooled arm relievedthe myotonia in a few minutes, during which timethe weakness did not improve or actually becomegreater.The rate of onset and recovery from paralysis due

to anoxia of the forearm was normal. The recoveryfrom weakness produced by cold was more rapid inthe arm which was ischaemic during the cooling.This suggested that during cooling some substancemight diffuse from the muscles into the blood orvice versa. However, we failed to detect any dif-ference in several chemical constituents in bloodtaken from the cooled arm compared with the un-cooled arm.

SummaryA man aged 51 years presented with a history of

myotonia aggravated by cold, of weakness induced bycold, of attacks during his youth resembling familialperiodic paralysis, and of progressive weakness andwasting of the muscles of his legs since the age of

45 years. The family history showed inheritance ofmyotonia as an autosomal dominant characteristic.

Investigation revealed the following features:-(1) Immersion in a cold bath caused general weak-ness and myotonia. Cooling of a forearm inducedlocal paralysis and myotonia. Power only recoveredafter many hours at room temperature or aboutone hour in hot water. Myotonia passed off in afew minutes in hot water. (2) Ischaemia duringcooling hastened the rate of recovery on rewarming.(3) Neostigmine caused myotonia, but no weakness.Quinine prevented and relieved myotonia. (4) Potas-sium chloride taken orally rapidly producedweakness.

The authors would like to express their thanks toDr. J. A. Loraine for the estimation of urinary gonado-trophin, to Dr. S. L. Tompsett for the chemical analyses,and to Dr. R. Alexander for the loan of the thermistor.

REFERENCESBickerstaff, E. R. (1953). Journal of Neurology, Neurosurgery and

Psychiatry, 16, 178.Biemond, A., and Daniels, A. P. (1934). Brain, 57, 91.Brain, W. Russell (1955). Diseases of the Nervous System, 5th ed.

Oxford University Press, London.Eulenburg, A. (1886). Neurol. Zbl., 5, 265.Kolb, L. C., Harvey, A. M., and Whitehill, M. R. (1938). Bull.

Johns Hopk. Hosp., 62, 188.Maas, O., and Paterson, A. S. (1950). Brain, 73, 318.McArdle, B. (1956). Brit. med. Bull., 12, 226.Marshall, J. (1952). Journal of Neurology, Neurosurgery and

Psychiatry, 15, 206.Ravin, A. (1939). Medicine (Baltimore), 18, 443.Russell, W. R., and Stedman, E. (1936). Lancet, 2, 742.Schott, E. (1935). Dtsch. Arch. klin. Med., 178, 255.Shy, G. M., and McEachern, D. (1951). Journal of Neurology,

Neurosurgery and Psychiatry, 14, 101.Stevens, J. R. (1954). A.M.A. Arch. Neurol. Psychiat., 72, 726.Talbott, J. H. (1941). Medicine (Baltimore), 20, 85.Thomasen, E. (1948). Myotoni: Thomsen's Disease. Universitats-

forlaget, Aarhus.Tyler, F. H., Stephens, F. E., Gunn, F. D., and Perkoff, G. T. (1951).

J. clin. Invest., 30, 492.Zabriskie, E. G., and- Frantz, A. M. (1932). Bull. neurol. inst. N. Y.,

2, 57.

46

Protected by copyright.

on August 24, 2021 by guest.

http://jnnp.bmj.com

/J N

eurol Neurosurg P

sychiatry: first published as 10.1136/jnnp.20.1.40 on 1 February 1957. D

ownloaded from